Process and apparatus for treating oil shales



June 19, 1923s. Y

I w.` K.. KIRBY A PROCESS' AND APPARATUS FORA .TREATINGIOILfsHA-LES Filed' sept. 19, 1921 ATTORNEYS.

sis.

Patented June 19, 1923.

UNlTEDI STATES WILLIAM K. KIRBY, 0F GULDEN, COLORADO.

PROCESS AND APPARATUS FOR TBEATING OIL SHALEB.

Application tiled September 19, 1921.

To wZZ whom t may concer/1.:

Be it known that I, WILLIAM K. Kinx, a citizen of the United States, residin at Golden, in the county of Jefferson and tate of Colorado, have invented certain new and useful Im rovements in Processes and Apparatus for I'Ireating Oil Shales, of which the following is a specification.

This invention relates to improvements in the art of obtaining shale oil, which improvements embody a novel process ormethod of and apparatus or system for treating oil shales, whereby the valuable constituents thereof are educed and conserved with rthe aims in view of maximum production, superior quality and comparatively minimum expense.

It is believed to be generally understood that all of the oil shales at least do not necessarily contain any substantial amount of oil per se, that is to say that oil may not be obtained therefrom by pressure or solvents, but when such shales are retorted they then give 0H, in addition to other values probably, certain gases and oily vapors, which latter may beV converted readily by proper methods into a liquefied state, or as valuable shale oil products.

It naturally follows, however, that the same oil shale might yield varying quantities and qualities of said shale oil products, largely dependent upon the manner in which the decomposition or destructive distillation of the oil shale is carried on, because any fixed or non-condensable gases formed are generated at the expense of the desired shale oil products.

Under former processes, in so far as I am aware, there has always been a large yield of fixed or permanent gases, owingto the extremely high retorting temperature requisite for decomposing lump shale, it -being understood that the, chemical and physical characteristics of oil shales are such as to render them very poor conductors of heat.- As before stated, the permanent gases thus generated are formed at the expense of the desired oil, not onl on account of the diminished yield of t e condensable products but also because of the inferior quality of the resultant oil, which under such conditions contains a high percentage of unsaturated hydrocarbons instead of the desired stable hydrocarbon compounds of the saturated or paran series.

Serial No. 501,788.

Also, there are many other objectionable features, under the methods or processes practised prior to my invention, some of which may be set forth briefly in that the oil yielded has not always been suitable for practical refining into commercial products, or that when even partially suitable the yield has only been in the nature of one condensed crude oil, as distinguishedv from fractional jectionable features, in obtaining shale; oil

products as aforesaid, by an economical and eiicient method. However, as these and other objects and advantages will be so clearly apparent, as incidental to the following disclosure, it would serve no useful purpose to further enlarge on the same initially, but it may not be amiss at this point to berifly state the broader embodiment of the invention as follows In the initial steps, a mixture of finely divided, ground, or pulverized oil shale and high boiling point oil, or other appropriate and analogously functioning liquid, are caused to low through 'a pipe coil retort and, while flowing therethrough, this mixture is heated to the required temperature for the proper vaporization of the vaporizf Aable constituents of the oil shale, and this mixture may be thus retorted with or without the addition of, although preferably as" associated with, a suitably introduced continuous stream of either steam or permanent gas, or both, or their equivalents if any. Subsequently, the vapors arising during` this or any later steps of the process are conducted through suitable liquefying steps. The object of mixing high boiling point oil with the finely comminuted oil shale is that the former serves as a carrying or vehicle medium forthe latter, and the object of employing a pipe coil retort is that the small diameter of the pipe coil not only provides for al continuous flow of the mixture in a stream of comparatively or relatively small cross-sectional area, whereby it is effectively heated in a shortened length of travel, but the small diameter of the pipe coil also allows the mixture to traverse its heating zone at a high velocity, thereby avoiding the aforesaid objectionable features of local overheating and cracking, Which also are factors to be taken into serious consideration. The object of introducing permanent gas into the mixture is to provide, or saturate the internal heating zone with, an, excess of permanent hydrocarbon gas, thereby lessening the tendency to form fixed gases from the oil shale when heated, and the object of introducing live steam into the mixture is primarily for the purpose of assisting in circulating the mixture through the pipe coil retort. Also, it may be further stated that the oily vapors given off by the oil shale may be condensed by fractional cooling, into oil fractions which are suitable for refining into commercial products, in the one operation or series of steps, as distinguished from subsequent treatment for separation into the desired oil fractions, although the vapors may be liquefied in any other suitable Way.

Supplementing these prefacing remarks, the truel merits of the process can perhaps be better emphasized in narrative form and l concurrently with a description of an etiicient system or apparatus for carrying forward the steps thereof. To this end, therefore, reference will now be had to the accompanying drawings, illustrating certain practical embodiments of such a system, although it is to be understood that I do not restrict myself to the employment of all of the details thereof exactly as disclosed.

A In these drawings, the single figure is a diagrammatic view illustrating one such system, which view is partly in elevation and partly in vertical section, while some of the obvious elements are simply shown conventionally.

In the initial steps of the process, the pulverized or finely divided oil shale may be fed, by a chuteway or feed conduit, from a storage bin 1 to ahopper or feeder receptacle 2, which latter may provide a tubular discharge spout 3, containing a screw conveyer, in communication with a main conduit section 4 between the ends thereof, for supplying the said conduit section 4 witha regulated forced feed supply of the pulverized shale.

One portion of the conduit section 4 is in communication with a supply of any appropriate liquid, serving as a carrying medium or an entraining fiuid vehicle for the pulverized shale, which liquid is preferably a remesa high boiling point hydrocarbon oil, contamed in an oil storage tank 6, while the other portion of the conduit 4 is coupled up with a pump 5 which supplies a mixing chamber 8, by way of the pipe connection 7, with a continuous feed of pulverized shale and the high boiling point oil in desired proportions.

A branch conduit 11-12, having a pump 9 in its line, leads from a permanent hydrocarbon gas supply tank 10 to the mixing through the main conduit sections 13---15v and to and through theretorting zone. This retorting zone is preferably provided for by a pipe coil element 16 that is of relatively small or comparatively restricted cross-sec- Y tional area, say between approximately one to six inches inside diameter, for the reasons hereinbefore set forth.'

However, before actually retorting the aforesaid mixture, the latter may also be supplied with a continuous stream of live steam, as is desired, by way of a steam pipe line 14 in communication with the main conduit sections 13-15 between the ends thereof.

For the sake of convenience and brevity in terms, the expression oil vehicle, wherever herein appearing, is intended to be understood as referring to a high boiling point oil, and likewise the single word shale or the expression oil shale is intended to refer to the oil shales in a finely divided, ground, or pulverized state, when containing all or some of their locked up oily values, as distinguished from the finally spent shale or ash. Also, the main conduit section 4 may be appropriately referred to as an oil suction conduit, although in reality it is a suction conduit for both the shale and its entraining oil vehicle, and the conduit 11-12 may analogously be referred to as a gas suction conduit, while the pumps 5 and 9, respectively, may be appropriately referred to as an oil pump and a gas pump.

17 designates a suitable brick setting or furnace box providing the combustion chamber 18, enveloping the pipe coil retorting element 16, which may be fired either by an oil or other suitable burner associated with a burner opening 18, or by a grate fire as would be indicated by the fire box 18".

As before stated, either the permanent gas or the live steam or both of them are preferably introduced into entrained or entraining association with the shale and its oil vef` hicle. but whether they are or not the then existing mixture, which may now be apform.

Inasmuch asdmy process is, peculiarly adapted for the treatment of oil shales, 1 n the production of shale oil therefrom, 1t 1s to be understood that the operations ofthe apparatus, such as the regulation of temperature and the travel of the shale charge through the heating zone, are governed 1n accordance with the nature and condition of the oil shale being treated, in order to obtain the most satisfactory results. To such fends, therefore, observations should be made and the aforesaid regulations adjusted as occasions may require. Also, it may be stated at this point that my process may be conducted under atmospheric pressure or any pressure above atmospheric pressure.

-The proper pressure is determinable from the capacity of the retorting pipe coil and its length, as the pressure requlred is that which is necessary to pump the p repared charge through 'the pipe retortlng coil 16.

The gases of combustion finally pass from the chamber 18 of the furnace out through a stack 19, while the aforesaid flowing shale charge with its `unlocked oily vapors pass from the coil retorting zone to and along a continuing conduit 20, which is supplied with a suitably attached indicating thermometer as designated at 21, and which conduit has a terminal outlet opening downwardly into a vapor separator or liberating zone.

This vapor separator may consist of a tank 22 providing a domeshaped top and a downwardly converging bottom chamber 22a, between which are mounted suitable bafiiing elements 23. The baiing elements 23 may consist of the upper and the lower hollow upstanding cones and an intermediate inverted hollow cone that is truncated. A perforated coil 24 may be mounted in the'conical bottom chamber 22, and is supplied with superheated steam by way of the pipe line 25.

The aforesaid heated mixture, as it passes from the conduit 20, is discharged directly over and upon the apex of the upper cone baffle 23. The downward baffled course of the now substantially spent shale and the oil vehicle therefor is clearly shown, and during this stage of the operations the oily vapors are completely liberated and separated from thecharge.

The greater volu'me of the oily and other vapors, as well as the permanent gas, arise into the upper portion or collecting chamber of the vapor separator tank 22, and pass therefrom to a fractional air cooled condenser by way of the conduit 26, their separation from the shale and its oil vehicle having been aided and they being furtheru assisted in leaving the tank 22 by the superheated steam introduced through the perforated coil 24, as will be obvious. Any of the vapors or permanent gases which may happen to be trapped within the upper and lower baflie cones 23,'however, escape from the vapor separator tank 22, by way of the vertically disposed open-ended tubular arm 27a of a branchpipe 27, and enter the conduit line 26 leading to any suitable liquefying means, but illustrated as a fractional air cooled condenser.-

.This fractional air cooled condenser conslsts of the shell 28, spaced open-ended air tubes or flues 29l mounted by header plates providing end air chambers, alternating downwardly and upwardly disposed overlapping baie plates 30, and also upwardly disposed shallow partitioning walls 30a, which latter are employed for the purpose of dividing the lower portion of the shell 28 into a series of base drip receiving compartments 31. In the drawings these base compartments 31 have been illustrated as being four in number, and they function as the drip receiving chambers or channels for certain of the fractionally condensed distillates, it being understood that the heavier or more easily condensable vapors are divisionally condensed as the vapors and gases are tortuously diverted Iby the baffles 30 in their encompassing passage around the air flues 29 from the left to the right of the condenser, while air is being drawn from the right to the left through the ues 29 and passes out by way of a stack 32, the suction therethrough being The permanent gas, lighter shale oil va-4 1 pors and steam, which have not been condensed in the fractional air cooled condenser 28, leave the latter by way of the conduit 39 and enter a water cooled condenser 40. In this water cooled condenser, these remaining shale oil vapors, permanent gas and steam circulate around between the water tubes 41 thereof and are condensed, excepting of course the permanent gas, into lighter shale oil and water, both of which latter leave the condenser by the slightly upset conduit 42 leading to storage tanks, and this lighter shale oil is also in the form of a shale oil distillate that is suitable for refining into commercial products.

During this final step, the ermanent hydrocarbon gas is conducted o from the condenser 40 by a connecting pipe line 43 and is conveyed backy to the storage gas tank 10, by any suitable pipeline not shown, Where it enters at 43a to be used over again in successive operations.

Water enters the water cooled condenser 40 through the'pipe line 44 and leaves by the pipe line 45.

The spent shale and its oil vehicle flow by gravity from the conical bottom chamber 22, of the vapor separator 22, through a pipe line 46 which discharges into a settling tank 47, and the pipe line 46 may provide a cooling jacket 46a that may be supplied by cooling water through the pipe line 48, the

outlet therefor being indicated by the pipel line 49.

The pipe line 46 may also be provided with a valvular control or cut-ofi' 50, connected by suitable means 52 with afloat 51 disposed Within the se arator tank 22 at a suitable position with reference to its bottom, the object of which is to maintain a level of the spent pulverized shale and the high boiling point oil in the conical bottom of the vapor separator tank 22.

The cooled and discharged spent shale settles to the bottom of the settling tank 4T, and may be removed in any suitable Way, or even by a sediment cock line not shown, While the high boiling oint oil is pumped from the settling tank 4l; back to the oil vehicle storage supply tank 6, by Way of the pipe line 53-55 and a pump 54 included therein, to be used over again in successive operations.

From the foregoing complete description, it is believed that my improved process, and a satisfactory system for carrying forward the steps thereof, Will be clearly understood, and it may finally be observed that there are three stages of operation, as it Were, the treating' and retorting stage, the vapor separation stage, and the condensing stage.

For the most satisfactory results as a whole, l prefer to carry out my process as a continuous method embodying the particular nature of these stages in al conjointly coacting manner as herein set forth, yet the novel features of the initial treating and retorting stage could be satisfactorily employed in association with final condensing methods other than herein disclosed. Also, it is not altogether unlikely that some other specific form of vapor separating tank could likewise be satisfactorily employed.

lt is to be understood, therefore, that I do not wish to unnecessarily limit myself, viewed from various aspects. excepting in respect of the terms of the ensuing claims, equivalent features thereof. and as fairly interpreted in the light of the specification if necessary.

What I do claim -as new and patentable 1s:-

1. The process of producingpshale oil, which includes the steps of causing a properly `pro portioned charge of finely divided oil shale and an entraining hi h boiling point oil to flow in a stream o restricted cross-sectional area through an analogously restricted retorting zone, supplying heat to said retorting zone of an lntensity to liberate the desired values of said shale in the form of oily vapors, and subsequently liquefying said vapors as separated from said shale.

2. The process of producing shale oil, which includes the steps of causlng a charge of finely divided oil shale and an entraining.

high boilin point oil to flow in a stream of restricte cross-sectional area through an.

analogously restricted retorting zone, supplying a suitable charge of permanent gas to said oil shale charge before enterin said retorting zone, supplying heat to said retorting zone of an intensity to liberate the desired values of said shale in the form of oily vapors, and subsequently li uefying said vapors as separated from sai shale.

3. The process of producing shale oil', which includes the steps of causing `a charge of finely divided oil shale and an entraining high boiling point oil to `flow in a stream of restricted cross-sectional area through an analogously restricted retorting zone, 'sup-- plying suitable charges of both permanent gas and live steam to said oil shale charge before entering said retorting zone, supplying heat to said retorting zone of an intensity to liberate the desired values of said shale in the form of oily vapors, and subsequently liquefying said vapors asseparated from said shale.

4. The process of producing shale oil, which includes the steps of causing a properly proportioned charge of finely divided oil shale and an entraining high boiling point oil to flow through a retorting zone of winding .disposition and of restricted cross-sectional area, supplying a stream of permanent gas to the aforesaid char e, supplying heat to said retorting zone o an intensity to liberate the desired values of said shale in thev form of oilyvapors, and subsequently liquefying said vapors as separated from said shale.- Y 1 5. The process of producing shale oil, which includes the steps of'v causing a properly proportioned charge of finely divided oil shale and an entraining high boiling point oil to flow through a retorting zone of Winding disposition and of restricted cross-sectional area, supplying suitable streams of both permanent gas and live loo steam to the aforesaid charge, supplying subsequently liquefying said vapors as separated from said shale.

6. The process of producing'shale oil, which includes thc steps of causing a charge of finely divided oil shale and an entraining high boiling point oil to flow through a retorting zone of-restricted cross-sectionalarea, supplying heat to said retorting zone of an intensity to properly release the volatile values of said shale in the form of oily vapors, discharging the retorted charge in a continuous stream Within a separator zone, introducing superheated steam into said separator zone below said discharging stream, and conveying off from said separator zone the liberated oily vapors in volume separately of said high boiling point oil and the now spent shale charge.

7. The process of producing shale oil, which includes the steps of causing a proportionate mixture of iinely divided oil shale and an entraining high boiling point oil to iow through a retorting zone of winding disposition and of restricted cross-sectional area, supplying suitable streams of both permanent gas and live steam to the aforesaid mixture, supplying heat to said rctorting zone of an intensity to properly release the volatile values of said shale in the form of oily vapors, discharging the retorted charge in a continuous stream within a separator zone, introducing superheated steam into said separator zone below said discharging stream, conveying` ofi' from said separator zone the permanent gas and liberated oily vapors in volume separately of said high boiling point oil and the now spent shale,

conjointly conducting off said high boiling point oil and the spent shale for removal 'and separation purposes, liquefying said oily vapors, and conducting said high boiling point oil, after'separation from said spent shale, hack to its initial source of supply for cyclical reuse.

8. In apparatus for procuring shale oil from oil shale, the combination of a main conduit including a retorting pipe coil and a suctio'n conduit in advance thereof for flowing the charge to be retorted through said coil,'a tank for containing a supply of high boiling point oil in communication with said suction conduit, means for -feeding nely divided oil shale to said suction conduit, a tank for containing a supply'ofpermanent gas in suctional communication with said main conduit and a steam supply line for said main conduit in advance of said coil, means for heating said coil to such a degree as to properly release the desired values of said shale in the form of oily vapors,` a separator vessel for receiving the discharge from said coil` a vapor conduit for the liberated vapors and said permanent gas and a residue conduit for the spent shale and high boiling point oil leading from said separator vessel, means for liquefying the vapors conducted through said vapor conduit as desired, a conduit for returning said permanent gas to said gas trank, and a conduit for returning said high boiling point oil to said oil tank.

In testimony whereof, I aflix my signature.

WILLIAM K. KIRBY. 

